Making a new bromo-containing cellulosic dye with antibacterial properties for use on various fabrics using computational research

The reaction of cyanoethyl cellulose with para-bromo diazonium chloride resulted in the creation of a novel bromo-containing cellulosic (MCPT). The dispersion stability of MCPT has been improved by its dispersion into 1% waterborne polyurethane acrylate (WPUA). TEM, particle size, and zeta potential were used to track the dispersion stability of aqueous MCPT and MCPT in 1% WPUA and particle size. The prepared MCPT has been utilized as a unique green colorant (dye) for the printing of cotton, polyester, and cotton/polyester blend fabrics using a silkscreen printing technique through a single printing step and one color system. Color improvement has been achieved by printing different fabrics with a printing paste of MCPT dispersed in 1% WPUA. The MCPT and MCPT in 1% WPUA printed fabrics were evaluated for rubbing, light, washing, and perspiration fastness, UV blocking activity, and antibacterial activity. These findings were established through structural optimization at the DFT/B3LYP/6-31 (G) level and simulations involving several proteins.


Methods
Instruments. FT-IR was analyzed via Shimadzu FT-IR 8101 PC spectrum and the 1HNMR, 13CNMR were analyzed in DMSO solvent at 300 MHz on a Varian Mercury using TMS as an internal standard. UV-Vis spectrophotometer measurements were carried out by the JASCO V-730 UV-visible/NIR double-beam spectrophotometer, Tokyo, Japan. The scan was performed from 200 to 800 nm in DMSO as solvent. The SEM photos were detected using JEOL JXA-840A electron probe microanalyzer, and the samples were air-dried before captures were at voltage of 10-15 kV using FEI IN SPECTS Company, Philips, Holland. Moreover, TEM analysis were taken with a high-resolution JEOL JEM-2100/Japan. The samples were deposited from an aqueous dilute dispersion on a micro grid covered with a thin carbon film (≈ 200 nm). The Particle Sizing Systems (Santa Barbara Inc., California, USA) were used to estimate the particle size and zeta potential (ζ) of samples. The color strength (K/S) of printed fabrics was determined using the Mini ScanTM XE Hunter-Lab Universal Software, which is based on the equation of Kubelka-Munk: K/S = (1 − R)2/2R, where K denotes the absorption coefficient, S denotes the scattering coefficient, and R denotes the fraction of light reflected at a wavelength of minimum reflectance or maximum absorbance. CIE lab color parameter L* specifies the sample's brightness, a* and b* are chromaticity coordinates specifies the sample's redness-green and yellowing-bluish shift respectively 35 . The fastness property of washing, rubbing, perspiration, and light is evaluated using standard methods 36 . The UV protection factor (UPF) was calculated using a UV-Shimadzu 3101-PC-Spectrophotometer and the Australian/ New Zealand Standard (AS/NZS-4399-1996), a UPF value that less than 20 indicates poor protection, 20-29 indicates good protection, 30-40 indicates very good protection, and > 40 indicates excellent protection.

Reactivity of cellulose (1) with CH=CH-CN (2).
Microcrystalline cellulose (MCC) (1) (3 g, 0.018 mol) was mixed in 60 ml of sodium hydrozide solution (10%) at − 10 °C for 24 h to give a clear solution then the add the CH=CH-CN (2) (9 ml, 0.137 mol) dropwise to the solution of microcrystalline cellulose with stirring at 5-10 °C for 6 h. Lastly, the solution was neutralized with CH 3  www.nature.com/scientificreports/ solved in 30 ml pyridine, and addition was dropwise at 0-5 °C for half hour, then stirred for 4 h, and keep in fridge for 12 h, and diluted with water and formed solid collected and filtered off washed with water then crystallized with mixture EtOH/DMF afforded the corresponding hydrazone derivatives 4a.
Cyclization of the hydrazones derivative. Solution of hydrazone derivative 4a (1 mmol) in pyridine (15 ml ) was heated for 6 h, cooled and filtered off, washed with EtOH, and crystallized with DMF/H 2 O to give  MCPT(5a)  (2R,3R,4S,5R,6S) Synthesis of polymer waterborne polyurethane acrylate (WPUA). The synthesized of Waterborne polyurethane acrylate (WPUA) was obtained through a poly-addition reaction of polyethylene glycol (6000 g/ mol), isophorone diisocyanate, sorbitol as saturated hydrophilic chain extender (improve the adhesion between the PUA film and substrate) and the hydroxyethyl acrylate as UV reactive capping agent under inert atmosphere as the following 37 : In a flask with three necks fitted with a stirrer, a thermometer, and a reflux condenser under nitrogen, a calculated quantity of polyethylene glycol (6000 g/mol) and sorbitol (11:1) was added as in 70% acetone and left for approximately 1 h to ensure the full mixing of the reaction elements.
To cap the entire terminal NCO group, an appropriate quantity of HEA was progressively introduced into the reaction solution over 1 h at 60 °C, and then the reaction medium was stirred constantly for another 2 h frequently at 60 °C. The end result was a clear solution of polyurethane acrylate.
Printing paste recipe, technique, and fixation. The paste used in fabric printing was made with 4% synthesized MCPT or MCPT in 1% synthesized WPUA and 1% ammonium persulfate and a synthetic thickener of 4 g/100 ml. The prepared printing pastes were homogenized and used for silk screen printing of the fabrics. The printed fabrics were thermo-fixed in an automatic thermostatic oven for 5 min at 160 °C before being washed in cold water, hot water, and then cold water again to remove any excess thickener or unreacted materials.
Antimicrobial activity. Antibacterial activity of printed fabrics of (MCPT) and (MCPT dispersed in 1% of WPUA) against Pseudomonas aeruginosa and Salmonella Typhimurium (−Ve bacteria), Bacillus subtilis, and Enterococcus facials (+Ve bacteria) was studied in vitro using nutrient agar medium. The tested sheets were located on the surface of the solidified media plates, and the plates were raised at 37 °C for 16-24 h. The activities were calculated by comparing the inhibition zone (IZ) compared to the test antibacterial strain to standard. Molecular docking studies. Docking of cellulosic derivatives and different fabrics were analyzed through MOE program 38 and determine their energy affinity, bond length and attached amino acids, with different geometry which support with RMS gradient of 0.01 Å, and examined with protein's called Crystal structure of Escherichia coli MenB in complex with substrate analog, OSB-NCoA (PDBID:3t88) 39 , and Crystal structure of the tyrosine phosphatase Cps4B from Streptococcus pneumoniae TIGR4 (PDBID:2wje) 40 . Ten docking simulation were track via standard parameters and the confirmations were selected and built on the procedure of total statistics, E configuration, and appropriate with the related amino acids in pocket for each protein.
DFT studies. The DFT/B3LYP/6-31(G) level were used and optimized utilized the Gaussian 09 program 41 and its majority benefit DFT approaches that provide increase the computational accuracy without increasing computation time. All chemicals were imagined via Gauss-View interface 42 . The basic parameters were estimated with Physical parameters retrieved from files 43 .

Results and discussion
Preparation and analysis. Microcrystalline cellulose (1) react with CH=CH-CN in the presence of sodium hydroxide solution at little temperature furnished the corresponding microcrystalline cyanoethyl cellulose (MCEC) through Michael reaction and the number of nitrogen substitution with DS = 1.5 as revealed in Fig. 1. FT-IR of dye MCEC (3) displayed OH absorption band at 3461 cm −1 and C≡N band at 2265 cm −1 , 1 H NMR presented signals at δ 2.75 and 4.37 owing to CH 2 group, besides glygose protons in the region 3.07-3.83 ppm; correspondingly. The behavior of acetamide 3 with a diazonium salt to give Br-hydrazones 4. The IR spectra of the isolated hydrazones exhibited bands at 3520-3121 cm −1 corresponding to NH function groups and a C≡N absorption band in the region 2500 cm −1 , besides the strong C=O bands in the region 1720-1688 cm −1 . Br-Hydrazone 4 underwent an intramolecular cyclization in pyridine via Michael-type addition of the endocyclic NH of the hydrazones 4a to the triple bond of a C≡N function group to give the MCPT(5a) as displayed in Fig. 1. MCPT revealed FT-IR spectrum absence of C≡N group and the presence of NH 2 at 3360 cm −1 and C=O groups extending from 1671 to 1611 cm −1 , however, its 1 H NMR exhibited the attendance of D 2 O exchangeable proton in the area from 6.5 ppm as a result of the NH 2 at 7.35 ppm due to pyrazolo [

Interaction of WPUA and MCPT
synthesis of waterborne polyurethane acrylate (WPUA) and dispersion of the MCPT on WPUA. The WPUA was synthesized by poly-addition of polyethylene glycol (6000 g/mol) with isophorone diisocyanate, the polymer chain was extended using sorbitol as hydrophilic chain extander to improve the adhesion forces of the polyurethane films, and the reaction was further reacted with hydroxyethyl acrylate, which acts as a UV reactive capping reagent in the presence of (DBTD) (Di-butyl tin dilaurate) as a catalyst under nitrogen atmosphere. The spectral characterization of WPUA was confirmed through FT-IR investigation, as displayed in Fig. 4 as OH strecting and N-H broadband at 3361 cm −1 , st CH 2 , CH 3 , CH at 2900 cm −1 , C=H Stretching at 2737 cm −1 , C=O s tretching at 1171 cm −1 , st C-N Stretching at 1338 cm −1 , C-O-C Stretching at 1094 cm −1 and δ: N-H & δ: CH 2 at 1540 and 1496 cm −1 ; respectively as displayed in Fig. 4.
Furthermore, the dispersion of Br cellulose MCPT in 1% WPUA was utilized by the ultra-sonication probe for 2 min as a green tool to make a complete dispersion and separate connected Nano particles 44 . The plausible interaction between MCPT and WPUA occurred through hydrogen bond interaction, as displayed in the proposed mechanism Fig. 5. The FT-IR of MCPT in (1%) WPUA showed the different absorption bands at OH stretching vibration at 3340 cm −1 and also the NH group showed in same range at 3330 cm −1 , C=H the aromatic of phenyl ring appears at 2980 cm −1 , CH bending showed at 1460 cm −1 , C-Br showed at 810 cm −1 which showed the intramolecular hydrogen bond interaction between OH of MPUA polymer with MCPT and amino group which reduced at showed in Fig. 4. www.nature.com/scientificreports/ Additionally, as WPUA particles are well dispersed in aqueous media as dual colloidal systems, waterborne polyurethanes (WPUA) appear to be becoming more common as eco-friendly alternatives to conventional polyurethanes as dispersing and/or binding agents 45,46 . The dispersion stability and particle size of MCPT were tracked among MCPT aqueous dispersion and aqueous 1% WPUA. Figure 6A,B TEM images of MCPT aqueous dispersion demonstrated that the particles clumped together and accumulated even when subjected to ultra-sonication due to the particles' large surface area as a result of hydrophobic interaction 47 . Furthermore, MCPT dispersion in 1% WPUA interacted with the polymeric layer of WPUA via hydrogen bond formation. This interaction's steric repellent effect overcame the particles' tendency to collect, flocculate, or re-agglomerate, resulting in improved dispersion stability 47,48 . As a result, Fig. 6C showed Nano-sized well dispersed MCPT particles. Smaller particles with uniform and homogeneous distribution with a core shell-like shape appeared in the Fig. 6D as a result of the effect of ultrasonic waves on the MCPT in 1% WPUA dispersion.

TEM and DLS investigation.
Furthermore, the TEM results can be supported by the results obtained from the DLS parameters as shown in Table 1 [mean diameter (Ø), variance (PI), standard deviation (Sd), and average zeta potential (ζ)]. The zeta www.nature.com/scientificreports/ potential value designated the physical stability of the suspensions. It is known that the higher the negative or positive value of the zeta potential, the greater the stability of the suspension 49 . The outcomes displayed that the highest values of the zeta potential were recorded with the dispersion of MCPT in 1% WPUA and MCPT in 1% WPUA (2 min sonication), which indicates the sufficient stability of these dispersions.    50 . The interaction between MCPT and cellulosic fabric may be achieved through the formation of intermolecular hydrogen bonding and these results were showed in the following proposed Fig. 7A,B,C) which showed the presence of amino group and OH of cellulose in MCPT dye can be easily interact with the fabrics in the OH of polyester, Cotton and CO/ PET fabrics which gave stability and make staining of the dye on the fabrics. The FT-IR spectral of printed fabrics are illustrated in Fig. 8. The changes that occurred in the MCPT printed cotton spectrum may be a result of the interaction between cellulose-OH and MPCT-NH 2 , though hydrogen bond formation led to a reduction of absorption intensity bands around 3330 and 3270 cm −1 in the neat cotton fabric spectrum. The unbounded OH in WPUA could be the reason for the additional increase in the-OH absorption band in the FT-IR spectrum of MCPT in WPUA printed cotton fabric. Alternatively, the polyester fabric has no reactive functional group to interact with colorant material. The water-insoluble nonionic MCPT may be worked as a dispersed dye and MCPT particles can interact with the polyester chains due to their low dissociation in water. At the temperature of 130 °C or higher, thermal agitation reasons the polyester's molecular structure to developed more amorphous, allowing MCPT particles to enter and adhere to the polyester fiber by van der Waals and dipole forces 51 .
IR spectrum of neat and printed polyester fabrics may help to clarify this interaction. The fig demonstrated that there was virtually no difference in the spectrum bands of MCPT printed polyester from a neat one because the concentration of absorbed MCPT in the polyester fabric was too low to exhibit its excitation in the spectrum 52 . This might be related to WPUA's unbounded OH group. Furthermore, the situation is interesting somewhere in CO/PET fabric, because consists of both callouses and polyester fiber, where the two proposed mechanisms of interaction are predicted to occur, as seen in the spectra of neat CO/PET, MCTP, and MCTP in WPUA printed fabrics, as presented in Fig. 8. The Fig. 9 exhibited the photographic photos of printed cotton, polyester and specially blended (cotton polyester blend 50:50) fabrics by MCPT and MCPT dispersed in 1% WPUA (before and after ultra-sonication) using silk screen technique. The color strength (K/S) and CIE lab color parameters of printed fabrics were evaluated and illustrated in Table 2. According to the data, all printed fabrics with MCPT have a significant K/S value. Some improvement in K/S was observed with all printed fabrics after printing with  www.nature.com/scientificreports/ ultrasonic dispersion MCPT compared to those printed MCPT, which could be accredited to the reduction in MCPT particle size due to the ultrasonic effect leading to more color penetration. On the other hand, the printed fabrics with MCPT dispersed in 1% WPUA introduced more enhancement in K/S of prints due to the binding properties of WPUA (forming a thin film covering the colorant particles after curing and restricting their release or discharge), while there was no notable improvement in the value of the blend sample's color depth 53 . Although applying an ultrasonic dispersion of (MCPT in 1% WPUA) to the printing paste did not enhance the K/S values of polyester fabric, it achieved improve the K/S values of cotton and blend samples. All these changes in color Ultraviolet protection factor (UPF) evaluation. Table 3 demonstrates the ultra-violet shielding activity of printed fabrics by MCPT and MCPT in 1% WPUA before and after ultra-sonic action as UPF values. The synthesized MCPT has excellent UV-blocking activity with all printed fabrics, as shown by the UPF values, according to the findings. However, it appeared that the application of ultrasonic resulted in a reduction of UPF values of both polyester and CO/PET prints. The UV capping activity of the acrylate portion of polyurethane acrylate may be responsible for the enhancement of UPF values of the printed fabrics by MCPT in 1% WPUA 46 . Ultrasonic action of MCPT in 1% WPUA was also shown to reduce the UV protection value of cotton and polyester prints.
Fatness properties of dye. The fastness properties of printed fabrics are represented in Table 4. The results were printed samples with MCPT (2 min sonication) with good light fastness. Better light fastness was observed with samples printed by MCPT in 1% WPUA (the samples become darker). The washing and perspiration fastness showed values ranged from good to very good with printed fabrics with MCPT. Further improvement in fastness properties was observed with the fabrics printed by MCPT dispersed in 1% WPUA. This may be clarified by the fact that the printing process is a surface application and its major drawback is related to absorption

Biological action
Antibacterial investigation. The antibacterial action of fabrics was established compared to inhibitory properties on the development of G+ and G− bacterial strains as displayed in Table 5. The presence of NH 2 on MCPT and the OH groups in cotton increases the activity of antibacterial activity, so the action with cotton exhibited higher activity compared to all strains, while it exhibited less activity with polyester and a cotton/polyester blend, and no activity with polyester. Furthermore, the presence of MCPT with 1% dispersed WPUA polymer revealed that it increased the activity of printed fabric and showed excellent activity with all types of antibacterial strains. Also, the presence of polyurethane with MCPT increases the efficacy of polyurethane against antimicrobials, which depends on the nature and hydrophilicity of WPUA, which provides a good opportunity for friendly interaction with aqueous germ suspension, that improves the presentation of polyurethanes 54 . The result of the analysis revealed that the printed fabric efficiency against microbial species (gram-negative and positive bacteria) varies depending on the bacterial strain. However, the highest anti-microbial effect was detected against Bacillus subtilis, as shown in Table 5     www.nature.com/scientificreports/ Table 6 and Fig. 11 It was observed that the moderate required energy between MCPT/polyester fabric monomer with PDBID: 3t88 showed -12.422 kcal/mol and shortage bond length 1.58-3.22 Å and higher binding with cotton with the binding energy − 13.7446 kcal/mol due to electrostatic hydrogen bonding interaction and shortage length 2.05 Å and the lowest energy with CO/PET with − 11.156 kcal/mol and length 1.56 Å as showed in Fig. 11A Table 4. Fatness properties of printed fabrics by MCPT. Where, Alt = alteration St. = staining.

Rubbing
Washing Perspiration Acidic Alkaline

Alt
Pi = −Ӽ [5] S = 1/2 η [6] ω = Pi 2 /2 [7] ΔN max = − Pi/η [8] Besides, the enhanced structures exhibited non-planarity used DFT/B3LYP/6-31 (G) level which showed MCEC(3) less energy with (− 896.44 au), although the reactivity increase to − 3844.317 au attributable to occurrence of Bromine in a para location which extent the stability of compound MCPT(5a), as well as the µ of MCEC (3) offered the least 1.8320D with can simply energy separation and gave it ability to react again and increased in MCPT (5a) 5.8438D which gave it stability. Electronegativity (χ) defined the attraction of atom with pair of electrons and observed MCEC (3) exhibited a high charge with 6.194 eV as a result of the occurrence of cyanide group and has ability to react again. Correspondingly, hardness η(eV) designates the transformation of electron cloud density in the structure and presented the small range of MCEC (3) with − 1.282 eV to modification of electron cloud because of cyanide. chemical potential of heterocyclic attached to fabric and the facility to absorb more energy in range − 2.498 and − 6.194 eV which presented capability to accumulation energy inside them. ω directed electrophilic character and electron movement among donor and acceptor so, the MCPT(5a) displayed that higher electophiphilc atmosphere to captivate electrons with 3.428 eV, while MCEC (3) showed less ω with − 14.958 eV to not absorb more electrons and established their reactivity to formation the new heterocycles. The great gap will have high stability and low reactivity, although a little gap will have low stability and high reactivity 63,64 , as demonstrated in Fig. 11A. HOMO-LUMO calculated at the B3LYP/6-31G(d, p) basis set for glycoside compound MCEC (3) exhibited band energy gap = 2.5649(eV), though distribution of electrons in MCPT(5a) attached to p-Br benzene as a result of withdrawing character and higher stability of this dye with band energy gap 4.29619 (eV) as exhibited in Fig. 12B. The optimization of WPUA showed energy − 2789.6685 (au) and the difference in HOMO-LUMO was 2.5671 eV (59.19872 kcal/mol) and it showed the stability of this polymer and its dipole moment 11.6670D and indicate the easily charge separation as displayed in Fig. 12C and its electronegativity's and chemical hardness were 3.271 (eV) (75.431 kcal/mol), 1.284 (eV) (28.7796 kcal/mol); respectively and can easily to interact and make hydrogen bonding with MCPT, which confirmed experimental elucidation of this dispersant with each others 65,66 .
Moreover, the interaction of MCPT of polyester, cotton, and Co/PET fabrics was investigated in Table 7 and Fig. 12D,E,F respectively. The reactivity of Co/PET showed more binding energy with − 5935.7062 (au), and MCPT/Cotton with −5171.76432 (au) and less interaction of MCPT/polyester (− 4599.4298 au) and all of the interaction of MCPT with all fabric showed band gap energy between FMO is > 1 and take range 0.55-0.71974 (eV) and showed the reactivity of this fabric and can easily to stained in the fabric. The dipole moment of Co/PET showed the highest value of 18.4068D can easily of the separation of charge. Furthermore, (χ) electronegativity's MCPT/polyester showed a high value with 3.552 eV can indicate interaction again and the MCPT/Co/PET showed the lowest value with 0.2911 eV due to more interaction.
Also, hardness η(eV) specifies the amount of resistance electron cloud density change in the structure and presented the low range of all fabrics, and take a range of 0.276-0.360 eV and increasing value in softness for all fabrics with range 2.779 eV for cotton and 3.423-3.626 eV for polyester and Co/PET; respectively. The chemical potential (Pi) of this dispersant fabrics showed the least value with MCPT/cotton and indicated to staining of cotton fibers surface, and MCPT/polyester and MCPT/Co/PET with range − 3.552 eV, − 2.911 eV; respectively. The HOMO-LUMO electron cloud mostly appeared on the interaction between them and showed hydrogen bonding interaction 67 . Additionally, the hydrogen bonding interaction which introduced through electrophilic and nucleophilic active sites and were determined utilized ESP, MEP, which investigating the molecular performance and showed polarity of molecule with active sites in charge distribution in 3D and their know physicochemical parameters 68,69 . To expect active sites for electrophilic and nucleophile positions in the compound, molecular electrostatic potentials (MEP) were calculated via B3LYP/6-31G(d,p) basis set, as displayed in Fig. 13. The common of the −ve  Fig. 13. Additionally, the hydrogen bonding interaction which introduced through electrophilic and nucleophilic active sites and were determined utilized ESP, MEP, which investigating the molecular performance and showed polarity of molecule with active sites in charge distribution in 3D and their know physicochemical parameters [68][69][70] . To expect active sites for electrophilic and nucleophile positions in the compound, molecular electrostatic potentials (MEP) were calculated via B3LYP/6-31G(d,p) basis set, as displayed in Fig. 13. The common of the −ve regions and +ve charges of most of the interaction bond between cellulosic compound MCPT with polyester, cotton, and Co/PET were dispersed exclusive the pocket which designates their and established the biological estimation of them and dispersion of MCPT on the surface of the fabric as displayed in Fig. 13.

Conclusion
In this elucidation, we synthesized the novel Br-cellulosic dye fused heterocycles through the reaction of C≡N cellulose with diazonium salts to give MCPT dye which was confirmed through different spectral analysis, also MCPT dispersion in 1% WPUA improved its dispersion stability. the prepared MCPT dye effectively colored all of the polyester, cotton, and CO/PET fabrics with considerable color depth and good fastness properties. In the printing past, the application of MCPT dye in 1% WPUA dispersion improved the color fastness properties